Duplicating machine



April 1945. R. R. ROCKHILL DUPLICATING MACHINE Filed Dec. 23, 1940 2 Sheets-Sheet 1 INVENT/OR." APOJCOf i8 POC/(H/ZL Avail 1 I RQR. ROCKHILL 2,374,039

DUPLICATING MACHINE Filed Dec. 23, I940- 2 Sheets-Sheet 2 INVENTOR. P0860! R IPOC/(fl/ZL Patented Apr. 17, 1945 DUPLICATING MACHINE Roscoe R. Rockhill, Shorewood, Wis., assignor to Rex-O-Graph, Inc., Milwaukee, Wis., a corpo- Y ration of Wisconsin Application December 23, 1940, Serial No. 371,224

8 Claims.

This invention relates to duplicating machines, and more particularly to new and improved means for introducing a master sheet into a clamping mechanism on a duplicating'drum, releasably retaining a master sheet on the drum during work dispensing rotation thereof, and

effecting release of the mastersheet clamping means by reverse rotation of the duplicating drum.

The primary object of the present invention resides in the provision of new and improved means under the control of a single manually operable element, the operating crank of the machine, for efiecting the opening of the clamping means to permit theapplication of amaster sheet to the drum and for efiecting the opening of the clamping means to permit the release of the master sheet after the desired number of copies have been made therefrom.

A further object resides in the provision of new and improved means for introducing a master sheet into a sheet receiving opening formed in the duplicating drum. I

A further object resides in the provision of ing -a master sheet in a sheet receiving opening formed in the duplicating rim.

A further object resides in the provision of new and improved means for releasing. the master sheet clamping means to permit the discharge of a master sheet from the drum after the desired number of copies have been struck from it. a

Another object resides in the provision ofnew and improved means disposed to contact the master sheet clamping means on each revolution of the drum, the means being operative to permit unimpeded rotation of the drum in work dispensing direction and also operative to engage the clamping bar at a predetermined position in the rotation of the drum in the reverse direction-to ,arrest furthermovement of the bar and effect the release of the clamping ac'tion of the bar upon further movement of the drum in the last mentioned direction.

Another object resides in the new and improved arrangement of the clamping bar contacting means in such position that the arrested movement of the clamping bar results in the alignment of the sheet receiving opening in the drum with a master sheet guide plate disposed adjacent the duplicating drum, to iacilitate the of the clamping bar is arrested by contact between it and the clamping bar contacting means.

Another object resides in the provision of new and improved clamping bar contacting means adapted to be maintained in operative position at all times by the action of gravity.

Another object resides in the provision of new and improved clamping bar contacting and actuating means that are simple inform, automatic in operation; free from mechanical difiiculties, inexpensive to produce and extremely eflicient in operation. I

Another objectreside in the provision of new and improved spring urged means for normally maintaining the clamping barin pressure contact with one side of a sheet receiving groove formed in a duplicating drum;

Another object resides in the improved arrangement of the master sheet guide plate, the master sheet receiving groove formed in the drum, the clamping bar, the clamping bar actuating means, and the operating crank of the duplicating machine whereby the position of the crank indicates definitely the position of the master sheet receiving groove and the direction of manipulation of the crank determines the function of the clamping bar contacting means, rotation in work dispensing direction results in unimpeded movement of the drum, while rotation in the reverse direction results in the automatic releasing action of the clamping bar atapredetermined point in the rotation of the drum to permit the release and discharge of the master sheet.

Other objects and advantages of the'present invention will become manifest from the following description of an illustrative embodiment of the invention shown in the accompanying drawings.

In the drawings:

Figure l is anoperators side elevational view of a duplicating machine embodying the teachings of the present invention;

Fig. 2 is a fragmentary vertical longitudinal sectional view through the discharge end of the machine taken substantially on the line 2'2 of Fig. 3;

Fig. 3 is a. vertical transverse sectional view taken on the line 3---3 of Fig. 2 and showing the associated relationship between the drum, clamping bar, master sheet guide plate and a clamping bar contacting element; r

Fig. 4 is a vertical sectional view .taken on the duced, and

Fig. is a detail sectional view taken on the line 5-5 of Fig. 3 showing means operative to effect release of the gripping action of the clamping bar.

The duplicating machine shown in the accom- A drum 16 including a cylindrical shell [1. and a pair of ends is secured to ashaft! that isjournalled for rotation in bearing elements 20 that are fixed in aligned openings 2| formed in the side walls of the body portion I0.

wallof the machine a sufficient distance to provide suitable anchorage for a crank arm 22 on which an operating handle 23 is mounted. The drum I6 is provided with a smooth polished surface that is interrupted by a relatively shallow longitudinal-1y disposed groove 24 adapted to receive a clamping. bar 25. The clamping bar 25 has a thickness'substantially equal to the depth One ex-. tremity of the shaft l9 extends beyond the sideand a copy sheet in the process of being progage a bar 36 secured to the side walls of the body portion to to retain the master sheet receiving tray in proper position upon the machine. The master sheet receiving tray 12 is provided with adjustably mounted guide plates l3 that are adapted to be positioned in a manner to accurately align the master sheet with the copy sheets which may be fed either manually or automatically from the sheet feed surface Il disposed adjacent the duplicating drum I6.

With a supply of blank copy sheets 4! positioned on the feed surface ll and a supply of of the groove 24 so as to conform with the cylindrical surface of the drum IS. The width of. the bar 25 is slightly less than that of the groove 24 so as to permit lateral movement of the bar within. thegroove 24. The length of the bar 25 is such that end portions 25 thereof extend beyond. the ends of the drum l6, for a purpose to be hereinafter more specifically described An aperture 2! is formed in the cylindrical portion ll of the drum. I6- midway between the ends thereof and the sameextends circumferentially from'the right hand edge of the groove 24 (as shown in Fig. 2). A second aperture 28 is disposed a short distance circumferentially from. the aperture 21. These holes21- and 28 serve to, receive the thumb and index finger respectively of the right hand of the operator so as to facilitate-manual manipulation of the clamping bar 25 if such be desired. A plate 29 is secured to the clamping bar 25 in any appropriate manner at a point midwaybetween the ends thereof so as to be directly beneath the aperture 21 when the clamping baris applied to the drum It. An ear 3|} preferably formed on the plate 29 serves'to receive one end of a tension spring 3-], the other end. of which is secured ad: jacent one end of a rod 32 that extends. radially from the shaft 19 and is secured thereto by means of a screw 33. The position of the spring 31 is such that the clamping bar 25 is normally retained in pressure contact. with the bottom and one side of the groove 24. The other end of. the rod 32 extends outwardly toward the inner wall of the shell: I 1 and terminates in a position such that it provides a stop to limitithe inward. movement of the free portion. of. the plate 29. A hole 34 formed in the plate 29 serves to receive the thumb of the operator so that the gripping bar 2.5 ma bedisplaced manually from contact with the side of the groove 24. As the thumb is introduced through the aperture'2'l into the hole 34, the index finger may be inserted into the aperture. 28 to retain the drum l6- against rotary movement during. the manual operation of unclamping the bar 25 i The master tray [2 is provid'edwi-thdownwardly and rearwardly' extending clips-35 (one of which. is shown); adapted to frictional-lymmaster sheets d2 positioned on the master tray -2 themachine is in readiness for operation. In

' order to introdu'cethe first master sheet into the groove 24' formed in the drum It, the operator may grip the. handle 23 and turn the crank 22 in a counterclockwise direction to a position in which further movement is impeded by contact between the end portions 26 of the. clamping bar 25' with the forward edges of' the lower ortions of arms, 33i that are pivotally mounted. on a rod 44 the ends of which are securedin the side walls ofthe body portion [0. The arms 43 are retained against lateral movement. by being positioned between a, shoulder 45 formed. on the rod .44 and a Washer. and nut 4.6 which is threaded on the rod 4'4. The arms 43 extend upwardly from the rod 44 and are provided. withv surfaces that contact a second rod ll. having. its ends anchored in the side walls ofv the body portion. Ill in a manner similar to. that of rod 44. The. arms 43 are designed to hang freely in a perpendicular position by the actionof gravity and their swinging. movement in one direction is. limitedv by their contact with the rod 4'! (see Fig, 2). With the crank 22 swung to the position previously mentioned, the ends 26 of the bar 25 are in Contact with the arms 43 which in turn arein contact with red 41- in a manner to arrest further movement of the bar 25. With the bar 25 retained against further movement with the drum, continued rotation of the crank 22 results in movement of the drum l6 relative to the fixed position of. the bar 25 and causes a sheet receiving opening to be formed between one side of the groove 24 and the adjacent side of the clamping bar 25. v

With the clamping bar 25 retained in its unclamped: position, the operator: may advance. the topmost master sheet 42 so that the leading edge thereof contacts the downwardly curved surface 48 of a guide plate 49 that is secured to the: rods 44' and. 41;. sheet 42' toward the guide plate 49 results in directing the leading-edge ofthe master sheet into.- the sheet receiving opening: formed between the clamping bar 25 and the side wall. of the groove 24; When the master sheet hasbeen fed a sufficient. distance to have the leading edge thereof. in contact with the bottom of the groove 24', the master sheet is in proper position to be clamped.v

The clamping actionis effected automatically by" means ofuthev tension of thespring 3| which reestablishes pressure contact between the'c'lamping bar 25 and the groove 24 when the operating handle 23 and crank arm 22 are moved in a clockwise direction. With the master sheet securel'y clamped on the drum It by action of the clamping bar 25, the copy sheets may be fed into the machine either manually or automatically to producethe desired number of copies of the material' contained on the master sheet; Whenthe Continued movementof the master desired number of copies'have been made, the master sheet may be removedby stopping the rotation of the operating handle'in a position just beyond its uppermost position in a course of rotation. I

The unclamping operation comprises the reversing of the direction of rotation of the operating handle to a point where the ends 26 of the clamping bar 25 again contact the lower portions of the arms 43 whereupon the tension of the spring is increased by moving the drum relative to the clamping bar 25 to relieve pressure contact between the bar 25 and the side wall of the groove 24. With the release of the clamping pressure between the bar 25 and the groove 24, the narrow marginal portion of the master copy will free itself from contact with the drum l6 and clamping bar 25 by reason of its inherent tendence to means in one direction, said pivotally mounted.

again assume its normal flat position. Rotation of the crank 22 in a clockwise direction will result in the dischargingof the master sheet on'top of the copy sheets 4| which have been directed onto the copy receiving tray l4 whichis secured to the frame ID by the insertion of'a downwardly directed flange formed on the forward edge thereof into a channel 52 formed on the upper edge ofaone end of the body portion ID. The remaining master sheets may be inserted individually in the manner previously described to permit the running ofi' of any desired number of copies of each of the master copiesat hand.

The position of the arms 43'is such that when the operating handle 23 is rotated ina clockwise direction to-produce the desired copies; the ends 26 of the clamping bar urge the arms43 in a direction in which they are free to move and hence the cyclic contact between th ends of the clampin bar and the arms 43 (asindicated in Fig. 5) does not impede, the normal operation of the machine. However, the operator is free at any time to discontinue the feed of the copy sheets and discharge the master than in use without as much as requiring a single extra turn of the operating handle 23; This feature adds greatly to the efiiciency of the machine and re sults directly from the inclusion of the new and improved means for effecting movement of the clamping bar 25 within the groove 24.

From the foregoing description it will readily be understood that a simple and effective master sheet clamping means has been provided for releasably retaining a master sheet in position on the drum of a duplicating machine. It should also be noted that the operation of clamping and unclamping the master sheet requires only the manual operation of a single element, the operating crank of the machine. By reason of this condition the efficiency of the duplicating machin has been greatly increased as the time consumed in adjusting, clamping, unclamping and discharging the master sheet has been reduced to the operation of the single element which is normally used for runnin off the desired copies of the material contained on a master sheet.

While the invention has been described in considerable detail in the foregoing description it is understood that various changes may be made in its embodiment without departing from or sacrificing any of the advantages hereinafter claimed:

I claim: a

1. In a duplicating machine the combination with a frame and a manually rotatable duplicating drum having a longitudinally disposed groove in the surface thereof, of a master sheet clamping means on said drum, said clamping means comprising a clamping bar receivable in said groove, said bar being laterally movable in said groove, means for normally retaining'said bar in pressure contact with the bottom and one side of said groove, and pivotally mounted means disposed adjacent each end of said drum for engaging said. bar upon rotation of said drum, means for limiting the movement of said pivotally mounted means being operative .upon'said bar upon rotation of said drum in one direction to engage said movement-limiting means to arrest movement of said bar to efiect the: release of clamping pressure between said bar and groove to provide an opening adapted to receive a master sheet, said pivotally mounted means being operative upon rotation of saiddrum in the opposite direction to permit unimpeded movement of said clamping bar and drum without; affecting the clamping contact between said clamping bar and said .groove.

2. In a duplicating machine the combination with a frame and a manually rotatable duplicatmg drum having a longitudinally disposed groove in the surface thereof, of a master sheet clamping means on said drum, said clamping means comprising a clamping bar receivable in said roove, said bar being laterally movable. in said groove,

means for normally retaining said bar in pressure contact with the bottom and one side 01' said groove, and pivotally vmounted means disposed adjacent each end of said drum for engagin said bar upon rotation of said drum, means for limiting the movement of said pivotally mounted means in one direction, said pivotally mounted ,means being operative'upon said bar upon rotation of saiddrum in onedirection to engage said movement limiting means to arrest movement of said bar While said drum is permitted continued movement sufiicient to effect the release of clamping pressure between said bar and groove to provide an opening adapted to receive a master sheet, said pivotally mounted means being operative upon rotation of said drum in the opposite direction to permit unimpeded movement of said clamping bar and drum without effecting the clamping contact between said clamping bar and said groove.

3. A master sheet clamping mechanism for duplicating machines including a drum and a manually operable drum rotating crank, said clamping mechanism including a longitudinally disposed groove formed in the surface of said drum, a clamping bar receivable in said groove, said bar being longer and .narrower than said groove,

means for releasably retaining said bar in said groove, .said retaining means operative to urge said bar into pressure contact with the bottom and one side of said groove, and pivotally mounted means disposed adjacent the ends of said drum for engaging the overhangin portions of said bar to arrest the movement of said bar upon rotation ofsaid drum in one direction to efiect the release of clamping pressure between said bar and one side of said groove, said pivotally mounted means being operative to permit unimpeded rotation of said drum and clamping bar in the opposite direction.

4. In a duplicating machine, the combination with a frame, a duplicating drum rotatably journalled in said frame, a duplicating drum rotatably journalled in said frame and having a longitudinally disposed groove formed therein, and am-anually operable means for rotating said drum, of a master sheet clamping means on said drum; saidiclampingmeans comprising a ban receivable in; said: groove, means for yieldably re.- tainingsaid bar pressure contact with the: bottom and; one side of. said groove; said. bar: having end portions extending; beyond said drum, means disposed adjacent: each. end; of said: drum. adapted to contact the. adjacent end; portion. of said. bar on each revolution of; said drum, said .means being operative to arrest the: movement of said bar and its. pressure: contact with said. groove. at a predeterminedposition of: rotation of said drum in onedirectiotr and having noefiect-on said bar upon rotation at said drum in the reverse: direction. c

; The combination in a duplicating machine of arotatable duplicating drumand master sheet clamping means on said drum, said: drum including a longitudinally disposed groove extend.- ingthe length of said*drum-,- a clamping bar receivabl'e in said groove, said clamping bar-having a thickness substantially equal to the depth of I said groove, a width narrower than said groove, and a length greater than said groove; yieldable means for retaining said clamping bar in pressure contact with the bottom and one side of said groove, and means disposed adjacent each endof said drum adapted tocontact the adj'acent end portion oisaid'baron each revolution of said drum; said: means being operativeto arrest movement of said bar and release-its pressurecontact with said groove at a predetermined position of rotation of said drum. in one direction and having no effect on said bar upon rotation of said drumin the reverse direction.

6. In a; duplicating machine the combination ing means onsaid drum, said clamping; means comprising a. clamping. bar receivable in said groove; said. bar being: longer than said. groove and. being laterally movable in saidgroove, means for normally retaining said bar in pressure con.- tact. with the. bottom and: one. side of said groove, with theends thereof. extending beyond the ends of said drum, rockably mounted. arms adjacent theends of said drum. adapted to lie in the path of travel of said. bar during the rotation of said drum, said arms being free to swing in one direction, abutmentmeans adaptedto limit the movement of said arms in. the reverse direction,. said arms being; adapted to arrest the movement of said bar at a predetermined.positionin the rotation of said drum in one direction wherein. said arms are in. contact.- withsaid abutment means with a frame and a manually rotatable dupli'cat.

ing drum having a longitudinally disposed groove in the surface thereof, of a master sheetclamping means on said drum; said clamping means comprising a clamping barreceivable in said groove, said bar being longer than said groove and being laterally movable in said groove-means for normally retaining said bar in: pressure con tact with the bottom andone side of saidgroove, With the ends thereof extending beyond the ends ofsaid drum, rockably mounted arms adjacent the ends oisaid drum adapted to liein the path of travel of said bar during the rotatio of said drum, said arms being adapted to arrest the movement or saidbar at a predetermined: position in the rotation of said drum in one direction toeffiect the release of clamping pressure between said barand said groove: thereby forming a master sheet receiving opening and said. arms being. operative upon rotation of saidldrum in: the reverse direction to permitcthe. clamping bar: to pass unimpeded with. said. clamping bar retained in master sheet clamping position.

7 In a duplicating machine the. combination with a frame and a manually rotatable duplicating: drum having a longitudinally disposed groove in the surface thereof, of a master sheet clamppass unimpeded. with. said clamping bar retained in master sheet clamping, position;

8: Ina duplicating machine the combinationwith. a. frame; a copy sheet support, a master sheet support, a master sheet guide plate, a manually rotatable duplicatingdrum, and a work receiving. tray,v of master sheet clamping means on said drum, said clamping means. comprising, a clamping bar, a longitudinally disposed groove in. said drum adapted to receive said bar, yieldable means for retaining said bar in said groove, said clamping bar beingv narrower than said groove whereby lateral movement of said bar may be effected in said groove, said clamping bar being longer than said groove thereby providing end portions that extend beyond said drum, means disposed adjacent the ends of said drum adapted to contact the endportions of said clamping bar on each revolution of said drum, said means serving upon rotation of said drum in one direction to arrest the movement of said clamping bar at a predetermined position in the. rotation of said drum wherein said groove and bar are in alignment with said. master sheet guide plate, means operative upon further. movement of said drum for efiecting the release of clamping pressure between said groove and said bar toform a master sheet. receiving opening therebetween; said opening being in alignment with said master sheet guide plate whereby master sheets fed against said platev will be directed into said opening, means for eiiecting the clamping oi saidmaster sheetbetweensaid bar and groove upon rotation of said drum in a reverse direction, said bar contacting :means permitting uninterrupted rotation of said drum in said last named direction without rendering: said. clamping: means inefiective ROSCOE R. ROCKHILL. 

